封闭液体界面因不均的电场和局部粒子力造成的变形
Faranaaz Rogier1, Wan Shao2, Yuanyuan Guo2
1Van 't Hoff Laboratory for Physical and Colloid Chemistry, Debye Institute for Nanomaterials Science, University Utrecht, Padualaan 8, Utrecht, 3584 CH, the Netherlands.
Journal of colloid and interface science
|December 12, 2023
概括
封闭的油水接口在电场下变形,曲率受油量影响. 在不稳定之前,电场可以显著增加接口曲率,像素壁或粒子的影响最小.
科学领域:
- 物理化学 物理化学
- 接口科学 接口科学
- 微流体学 微流体学
背景情况:
- 封闭的油水接口表现出取决于油量的曲率.
- 由于静电力和电场不均,电场会诱导接口变形.
- 了解这些变形对于微流体和界面现象至关重要.
研究的目的:
- 在电场下建模和测量封闭的油水接口的形状.
- 为了研究初始曲率,电场和限制对接口变形的影响.
- 为了确定像素壁和吸附粒子对接口行为的影响.
主要方法:
- 使用了理论建模和实验测量的组合.
- 模拟接口形状使用毛细管和静电原理.
- 测量了初始阴茎曲率,通过跟踪表面间被吸收的粒子和样本倾斜.
主要成果:
- 观察到的阴茎曲率半径在0.6-7毫米之间,表明最低油膜厚度为0.7-9微米.
- 证明电场可以在油膜不稳定之前将初始阴茎曲率增加高达76%.
- 发现像素壁和介面吸附粒子对接口变形的影响微不足道.
结论:
- 这项研究提供了对封闭的油水接口的电毛细血管行为的定量见解.
- 电场强度是控制接口变形和潜在不稳定的关键参数.
- 与这种系统中的静电力相比,封闭体几何和表面活性粒子在这个系统中起的作用很小.
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